[Audiology] Hearing in the dark

Intuitively it does seem as though I can hear better in the dark or if I
close my eyes. By that I think I mean that sounds I would not have heard
become audible. As my ears don't know it is dark I am guessing they work
at peak efficiency all the time and that the apparent improvement is a
function of shifting attention. So if I close my eyes or it is dark I
can devote more attention/processing power to the auditory input.
However, I have not managed to find any academic research in this area.
It may be I am using the wrong words to search. Does anyone know if this
subject has been formally researched and if so where I might look for
references?
Thanks for your time
Vic
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